Control valve arrangement for hydraulic motors



C. E. KURTZ Aug. l2, 1969 CONTROL VALVE ARRANGEMENT FOR HYDRAULIC MOTORS Filed Sept. 28, 1967 4 Sheets-Shed; 1

INVENTR (T/@77S E. KUPTZ ev ATTORNEY C. E. KURTZ Aug. 12, 1969 CONTROL VALVE ARRANGEMENT FOR HYDRAULIC MOTORS 4 sheets-sheet 2 Filed Sept. 28. 1967 C. E. KURTZ ug. l2, 1969 CONTROL VALVE ARRANGEMENT FOR HYDRAULIC MOTORS Filed Sept. 28. 1967 4 Sheets-Sheet 3 Aug. 12, 1969 c'. E. KURTZ 3,460,347

CONTROL VALVE ARRANGEMENT FOR HYDRAULIC MOTORS Filed Sept. 28. 1967 4 Sheets-Sheet 4 3,460,347 CONTROL VALVE ARRANGEMENT FOR HYDRAULIC MOTORS Curtis E. Kurtz, Arlington Heights, Ill., assigner to Borg- Warner Corporation, Chicago, Ill., a corporation of Illinois Filed Sept. 28, 1967, Ser. No. 671,320 Int. Cl. Flh 39/44; F01c 9/00 U.S. Cl. 60-52 6 Claims ABSTRACT F THE DISCLOSURE This invention relates to a control valve arrangement for hydraulic motors of the reciprocating type such as employed in operating vertically disposed agitators of fabric-treating machines.

Prior hydraulic motors of the reciprocating type may employ vanes oscillatable by hydraulic fluid pressure alternately admitted to and exhausted from opposite sides of the operating vane under the control of a valve shifted mechanically by the vane or hydraulically by fluid under pressure directed to the valve by the vane, upon completion of each stroke of the vane. In the operation of such hydraulic motor control, it is important that the valve be controlled to guard against the valve becoming locked or inoperative on dead center so that the motor is immobilized. Such occurrence may result when the valve includes a movable control member in the valve chamber connected to passages for introducing uid under pressure alternately to one end of the chamber to shift the member while fluid is exhausted from the other end of the chamber. In this example, movement of the vane to each of its extreme positions will signal the respective passages, i.e. one of the passages will receive fluid under pressure to shift the valve while fluid is exhausted from the other passage. If the signal is false because there is leakage between the passages with one passage providing initial pressure to one end of the valve, as soon as the exhaust signal is reached for the other passage, the valve member will only partially move so that the motor fails to operate or shortens the stroke of the agitator.

As a solution to this problem, it has been proposed to insure intsantaneous movement of the valve member to each of its control positions involving maintaining the valve in either of its extreme control positions until sufciently high pressure is built up to tire the valve member` to its other position, thus providing a toggle-like action to the valve member to control the ow of fluid under pressure to alternate sides of the vane of the motor.

To provide this advantageous feature, mechanical toggle-action controls for the valve have been proposed including ball or spring-activated detents engaging the valve member, or over-center springs connected to the valve member, to prevent movement of the valve member until the pressure of the uid became sufcient to overcome the mechanical controls and to insure firing of the valve member with a snap-action to each of its control positions.

An object of the present invention is to provide an improved control valve arrangement for hydraulic motors.

tes et Another object of the present invention is to provide a control valve arrangement for hydraulic motors in which a valve is reciprocal by a primary constant pressure between two motor-controlling positions; a secondary constant pressure being operative on the valve, during movement of the valve in either direction, to provide additional force to the valve, to insure movement to and location of the valve in the respective motor-controlling positions.

Another object of the invention is to provide an improved control valve arrangement for hydraulic motors in which a valve member is reciprocal in a valve chamber to two motor-controlling positions by fluid under pressure admitted alternately to ports at opposite ends of the chamber; the valve employing additional ports in the chamber and spaced from the ends thereof and connected to a source of Huid under constant pressure, movement of the valve uncovering respective of the additional ports to provide a supplemental force to insure valve movement to its desired position.

Another object of the present invention is to provide an improved control valve arrangement for hydraulic motors of the oscillating vane type and having a valve movable to two positions respectively controlling flow of fluid under pressure alternately to opposite sides of the vane to oscillate the vane, valve movement being controlled by fluid under pressure directed by the vane to the valve and also by uid under pressure directed to the valve, independently of the vane, to insure movement to each of its vane-controlling positions. Another object of the present invention is to provide an improved control valve for a hydraulic motor of the oscillating vane type adapted to operate the agitator of a fabric-treating machine and in which the valve includes a spool reciprocal in a chamber between two positions connecting a source of fluid under pressure alternately to opposite sides of the motor vane to oscillate the vane, the vane controlling ports connected respectively to opposite ends of the spool and directing fluid under pressure alternately through the ports to move the spool, and additional ports in the chamber and connected to the source of uid under pressure to provide additional supplemental pressure to the valve spool to insure snapacting movement of the valve spool to each of its vanecontrolling positions and providing an hydraulic toggle effective to prevent partial movement of the valve, due to leakage between the chamber ports, to a dead-center position to disable operation of the motor or create a short stroke of the vane and thereby the agitator, and also providing for substantial instantaneous reversal of the direction of rotation of the agitator for best washing action.

Further objects and other advantages of the invention will be more clearly apparent from the following specilication taken in connection with the drawings in which:

FIG. 1 illustrates a clothes washer having a hydraulic transmission embodying a preferred form of hydraulic motor-control valve arrangement of the present invention;

FIG. 2 is a vertical sectional view of the transmission and showing a pump, vane motor and valving of the transmission, said section being taken on line 2-2 of FIG. 3;

FIG. 3 is a horizontal view of the vane motor and portions of the valving of the transmission, taken on line 3 3 of FIG. 2;

FIGS. 4 and 5 further illustrate the valving including plates having fluid ports and passages for the valving disclosed in FIGS. 1, 2, and 3;

FIG. 6 is a bottom view of the vane of the vane motor shown in FIGS.1, 2, and 3;

FIGS. 7, 8, and 9 are schematic views of the hydraulic transmission illustrating the hydraulic components during various phases of the wash-agitate operation.

Referring to the drawings, my improved valve control arrangement for hydraluic motors of the reciprocating type is shown, in its preferred embodiment, in a hydraulic transmission 10 for a clothes-cleaning machine or washer 11 shown and described in my co-pending application, Ser. No. 661,760, filed Aug. 8, 1967, now Patent N0. 3,388,569, issued June 18, 1968. The washer 11 has an oscillatable agitator 12 to wash the clothes and a clothes container or basket 13 rotatable to extract washing liquid from the clothes.

The washer comprises a cabinet or casing 14 supporting a water container or tub 15 enclosed at its bottom end by a bulkhead 16 and a flexible rubber inverted cupshaped member 17 overlying a central opening in the bulkhead and having an annular ange 18 connected to the opening-defining peripheral edge 19 of the bulkhead and in water-sealing thereto.

The basket 13, agitator 12, transmission 1t), and a transmission drive shaft 20, are supported on a cylindrical steel mounting member 21 having its upper peripheral edge defined by a llange 22 extending between and connected to the flange 18 of member 17 and bulkhead edge 19. More particularly, the drive shaft extends through the members 21 and 17 and is rotatably mounted on the member 21 by a ball-bearing assembly 23. The bearing assembly 23 provides a radial and thrust bearing and, for this purpose, there is disposed between and engaging the outer race 24 of the assembly 23 and the inner cylindrical surface of the member 21, an annular resilient bushing 25 of rubber or the like. The bushing 2S is mounted on a radially inwardly directed annular peripheral flange 26 of the member 21. The outer race 24 is substantially Z-shaped in cross section with its lower inwardly extending annular flange 28 thereof engaging the bottom of the bushing and the top flange 29 overlying the top of the bushing. It will be apparent that the described mounting arrangement provides for the basket, agitator, transmission and its drive shaft, being flexibly and solely supported at a point near the lower end of the drive shaft. Disposed within the upper opening of the ilexible member 17 and surrounding the drive shaft 20 is a roller-bearing assembly 31, the member 17 having a cylindrical flange engaging the outer race of the assembly 31, the inner race of the assembly being secured to the drive shaft. The flexible member 17 is effective to vertically align the bearing; assemblies 23 and 31 and resistively permits gyratory movement of the basket, agitator and transmission, about the lower end of the drive shaft due to an unbalance load during rotation of the basket.

The drive shaft is connected to a reversible electric motor 32 pivotally supported on the cabinet and extending upwardly into a pocket 33 formed in the bulkhead 16. The motor 32 has a drive pulley 34 connected by a belt 35 to a pulley 36, secured to the end of the drlve shaft 20 and to a pulley 37 connected to a water pump 38 provided for exhausting water from the tub through an opening in the bulkhead 16 during rotation of the basket.

Referring to the hydraulic transmission, and specifically to FIGS. 2-9, inclusive, illustrating my improved hydraulic motor control valve arrangement, important elements of the hydraulic transmission are a reversible fluid pump 40 having its housing connected to the basket; a vaue-type hydraulic motor 41 for driving the agitator; control valving 42 for the motor 41; a lock mechanism 43 for the basket 13; and spin-control valves 44 and 45. A lid 46 closes the top opening in the cabinet 14.

A fluid sump 43 is shown in FIG. 2 and schematically illustrated for convenience in various places in the schematic views of FIGS. 7, 8, and 9, although in actual construction one fluid sump 48 is provided into which all of the exhaust connections for various elements of the transmission exhaust pressure.

Referring now more particularly to the transmission components, FIGS. 1-6 illustrate the structural components and their assembly in the transmission, while FIGS. 7-9 schematically identify the components in their operative relation to each other and to the agitator and basket and the drive motor and with particular reference to the fluid passages interconnecting the components in the performance of their functions.

In general, and as shown in FIGS. 1-6, the transmission structure comprises a unitary assembly adapted to be drivingly connected to the agitator 12 and to the basket 13 at its upper end and to the drive shaft 20 at its lower end. More particularly, and as shown in FIG. 2, the transmission structure comprises a housing 56 provided by top and bottom annular plates 57 and 58, and a cylindrical collar 59l extending between the plates and having its top and bottom edges received within circular' grooves 60, 61 respectively formed in the plates to provide the sump or reservoir 48 for the hydraulic fluid. Seals 62 and 63 are positioned in the grooves and engage the collar to confine the lluid in the sump 48. The housing 56 contains, and its top and bottom plates 57 and 58 confine, the operating components of the transmission including the vane motor 41; the valve block 64 containing the control valving 42, 44 and 4S; hydraulic lock mechanism 43; and the pump 40. A plurality of bolts 65 extend through and connect the plates 57 and 58, the vaned motor housing, and valve block 64 to confine the vane motor 41, the valve assembly and pump 40 therebetween. A plurality of pins 65a are provided to connect the valve block 64, and top and bottom pump plates 69b, and 69C and ring 69a, to the transmission housing plate 58, each pin 65a extending through aligned openings in these members to prevent relative movement thereof.

The pump 40 is a positive displacement pump of the conventional gerotor type having (FIGS. 2 and 7) an inner rotor 67 keyed to the drive shaft 20, and an outer rotor 68 rotatable in a housing. The housing comprises the cylindrical ring 69a surrounding the rotors, and the top and bottom plates 69h and 69C. The outer rotor 68 is provided with recesses 70 therein adapted to receive the teeth 71 on the inner rotor 67. As seen in FIG. 7, rotation of the rotors in a clockwise direction, during the agitate cycle, causes iluid to enter the pump through the port 72 (FIGS. 2 and 7) in the housing plate 6917 and, in a well-known manner, will act in the fluid chambers between the teeth 71 of the inner rotor and the recesses 70 of the outer rotor to provide fluid under pressure to a port 73 in the housing plate 6911. Upon rotation of the rotors in a counterclockwise direction, the rotors are effective to cause fluid to enter the pump through port 73 and to provide fluid under pressure to port 72.

The hydraulic motor 41 is shown structurally in FIGS, 2, 3, and 6 and schematically in FIGS. 7-9 and is a reversible or reciprocating type, selected for purposes of illustration, as an oscillating vane motor. This motor comprises a body 74, defining with top and bottom iluidpassage plates 75 and 76, a :tluid chamber in which is received the vane 78 connected to the agitator shaft 79. The body 74 has a wall 8? of frusto-conical shape projecting radially inwardly into the chamber and dividing the chamber into two portions 77a and 77b. The wall 80 has its apex formed arcuately concave to engage the cylindrical side portion of the vane 78 to provide, with the vane, the expansible and contractible fluid chamber portions 77a and 77h. The vane 78 reciprocates as fluid under pressure is admitted alternately to opposite sides thereof into the chamber portions 77a and 77b to oscillare the agitator during the washing cycle. As seen in FIG. 2, the vane is formed integral with the agitator shaft 79 journalled in the top cover plate 57, the portion of the shaft 79 extending below the vane is journalled in a central opening 81 of the valve vblock 64. The vane has an arcuate tip conforming to the cylindrical interior surface 82 of the body 74, and, as shown in FIG. 6, the tip is provided with a recess receiving a spring 83 and plunger 84, the spring actuating the plunger into engagement with the surface 82 to preclude fluid ow between the chamber portions 77a and 77b. It may be noted that the top cover plate 57, plates 75 and 76, and vane 78, contain various fluid ports and passages cooperating with ports and passages in the valve block 64, positioned between the vane motor and the pump, in a manner later to be described.

The valve block 64, as shown in FIGS. 3 and 5, contains the control valving 42 including a spool 86 reciprocable in a tangential bore or chamber 87 in the valve block under the influence of uid pressure controlled by the vane 78 to direct fluid under pressure into one of the chamber portions 77a or 77b while simultaneously exhausting the fluid in the other chamber portion, to reciprocate the vane. More particularly, and referring to FIGS. 3, 5, and 7, the spool 86 is provided with lands 88, 89, and 90, the lands 88 and 89 vbeing separated by a groove 91 and the lands 89 and 90 being separated by a groove 92. The ends of the bore are provided with plugs 93 and 94. The spool is shiftable in the bore 8-7 by uid under pressure supplied successively to opposite ends of the spool.

Referring to FIGS. 3, 5, and 7, the area of the valve body body around the valve 86 includes ports 95, 96, 97, 98, 99, 100, and 101. Fluid conduit 102 is connected to port 98. Conduits 103 and 104 are connected to ports 96 and 100, respectively, and are exhaust ports connected to the sump 48. Conduits 105 and 106 are connected to ports 95 and 101, respectively. The valve block is also provided with an arcuate groove 107 communicating with a pocket P in the block leading to the sump 48. The pocket (FIGS. 2 and 5) contain the valve 45 comprising an arcuate portion of the block engaging the plate 69b and defining a chamber C having an upper opening closed by a hemispherical button-like valve member 8 actuated by a spring 9. The chamber C is connected to port 72 of the pump 40.

As seen in FIGS. 2 and 6, the bottom of the hub 78a of the vane 78 is provided with two radially-spaced arcuate grooves 118 and 119 adapted to be connected to conduits 102, 105, 106, and 107. As seen in FIG. 2, the plate 76 is positioned between and its top side contacts the vane and housing of the vane motor and its bottom side contacts the top of the valve block 64. To afford uid communication between the valve block and vane motor iiuid chambers, the plate 76, as seen in FIGS". 3 and 4, is provided with circular openings 108, 109, 110, 111, 112, 113, 114, 115 and rectangular openings 116 and 117. The openings 108 and 112 are located at opposite ends of the arcuate passage 107 in the valve block and are connectible to the arcuate groove 118 in the vane hub 78a (FIGS. 2, 6, and 7). The openings 110 and 115 are located respectively at opposite ends of the arcuate channel 102 in the valve block and are connectible to the arcuate groove 119 in the vane hub 78a. The openings 111 and 113 are located respectively at the radially inner ends of the passages 105 and 106 of the valve block and are connectible to the arcuate groove 118 in the vane hub 78a. The openings 109 and 114 are located respectively above the passages 105 and 106 of the valve block and are connectible to the arcuate groove 119 in the vane hub 78a. The openings 116 and 117 in the plate 76 are located to connect these openings with the ports 97 and 99, respectively, in the valve block 64, the openings 116 communicating with the chamber portion 77b and the opening 117 communicating with the chamber portion 77a to direct fluid under pressure to one or the other of the chamber portions, dependent on the position of the spool 86.

During rotation of the vane, the passage 107 in the valve block functions to exhaust fluid from one end of the valve spool via one of the passages 105 or 106 while fluid under pressure is admitted by the other passage or 106 to the other end of the spool to shift the spool and thereby cause fluid under pressure to flow through opening 116 or 117 to one side of the vane while exhausting fluid through the other opening from the other side of the vane. In this manner, the vane motor controls the operation of the spool to direct uid to, and exhaust uid from, the motor chambers 77a and 77b to oscillate the vane.

Referring to FIGS. 2 and 7, the valve block 64 is provided with a passage 120 extending between and connecting the pump port 72, via chamber C, with the port 73 of the pump. The valve 44 is located in the passage 120 and comprises a valve member 121 slidably positioned in the passage and controlling flow of iuid through the passage. The valve member 121 is square in cross-section and has a beveled end 122 in complementary engagement with a portion of the block, defining the passage, to prevent flow of fluid through the passage and, for this purpose, a hairpin spring 123 is located in a recess in the block and extends itno the passage to engage the valve member. Fluid under pressure, from port 73 of the pump, enters the passage 120, but is precluded from flowing through the passage by the valve 44. When uid under pressure, from pump port 72, ows into the passage 120, the valve member 121 is shifted to the right (FIG. 2) against the action of spring 123. The member 121 is provided with a groove 124, in the top surface thereof, to restrict uid flow to the pump port 73.

It will be apparent that, during rotation of the pump in one diretcion, suction of the pump causes fluid to flow from the sump 48 into the chamber P, through valve 45, into the pump port 72 and through the pump where the uid is pressurized and flows from the port 73 into the valve 42, and also into passage 120 where the fluid is blocked by the valve 44. During rotation of the pump in a reverse direction, the valve 45 is closed and valve 44 opens and its groove 124 throttles the fluid to hydraulically couple the pump housing the rotors for a purpose to be described.

A relief valve 125 (FIGS. 5 and 7) is provided in a passage 126 extending between the sump 48 and the valve port 98 to control the pressure of the uid from the pump to the vane motor and spool valve 86.

Referring to FIG. 2, the -transmission housing top plate 57 contacts the bottom wall 126 of the basket and is secured thereto by bolts 127 extending through the basket wall and into the top plate 57 so that the transmission housing is secured to the basket. To prevent rotation of the basket and transmission during the washing-agitato operation, the transmission plate 58 is provided with the hydraulically-operated lock mechanism 43 having a plunger 129 actuatable to enter one of a plurality of openings 130 in a stationary at plate 131 secured t0 the top of the flexible member 17 as shown in FIGS. l and 2. The openings in plate 131 are circumferentially spaced about the drive shaft 20. When the plunger 129 is moved downwardly, it enters one of the openings 130 to connect the plate 131 to the transmission housing and thereby to the basket 13 to prevent rotation of the basket during the wash-agitate operation. Referring now specifically to FIG. 2, the plate 58 has aligned bores 132 and 133, the ybore 132 containing a spring 134 acting against the head of the plunger 129 to raise the plunger above the opening 130 in the plate 131. The -bore 132 is connected to the pump port 73 in the pump so that, upon rotation of the pump in a clockwise direction (FIG. 7) during the wash-agitate operation, iluid under pressure from port 73 is applied to the head of the plunger to move the plunger downwardly into an opening 130. Upon rotation of the pump in a counterclockwise direction during the spin-extract operation, fluid pressure is relieved on the plunger and the spring 134 raises the plunger to disconnect the basket from the plate 131.

Reference is now made to FIG. 7, for an explanation of the operation of my improved transmission. FIG. 7 is a schematic disclosure of the transmission in its relation to the agitator, basket, and drive motor. Assuming the electric motor 32 is energized and rotates the drive shaft 20 and the pump rotors 67 and 68 in a clockwise direction, uid under pressure is directed to the valve 42, and thereby to the vane motor 41; to the hydraulic lock mechanism 43 to position the plunger 129 in the stationary plate 131; and to the relief valve 125. The valve 44 is closed. Suction of the pump causes fluid to be drawn from the sump 48 through valve 45 and into the port 72 of the pump.

In FIG. 7, the spool 86 of valve 42 controls pressure fluid owing from port 73 of the pump through port 98 of the valve to direct the fluid through groove 92 of the valve spool, port 99, opening 117 in plate 76, into the chamber portion 77a of the vane motor to effect movement of the vane 78 in a clockwise direction, Also, the vane has its groove 119 connecting passages 114 and 115 in plate 76 to passage 102 in valve block 64 connected to groove 92 of the spool 86 so that -fluid under pressure from groove 92 flows through port 114 and passage 106 in the valve block to the left end of the spool 86. Also, vane 78 has had its groove 118 connect openings 108 and 111 in plate 76 to provide a uid exhaust passage from the port 95 and passage 105 in the valve block 64, connected openings 108 and 111 in plate 76, groove 118, groove 107 to the chamber P and sump 48. The vane 78 and thereby the agitator will be driven in a clockwise direction. During this vane movement, iluid in chamber portion 77b is exhausted through opening 116 in plate 76, port 97, groove 91 of spool 86, port 96, to sump 48.

Referring to FIG. 8, the vane has now moved from the position shown in FIG. 7 to that shown in FIG. 8. At this time, pressure uid in chamber 77a causes continued clockwise movement of the vane, while control grooves 118 and 119 are out of registry with the ports in the valve plate 76.

FIG. 9 illustrates the position of the vane at the termination of its clockwise movement and, in this position, the groove 119 is in registry with the openings 109 and 110 in the plate 76, and groove 118 connects openings 112 and 113 in plate 16. To obtain movement of the valve spool 86 from the position shown in FIG. 8 to its FIG. 9 position, pressure iluid flowing from pump pressure port 73 through groove 92 in spool 86, and port 98 and groove 102 in valve block y64, is directed through opening 110, groove 119 in the vane, to opening 109 and groove 105 into port 95 to cause movement of the spool from its FIG. 8 position to its FIG. 9 position. At the same time, it will be noted groove 11.8 of the vane connects ports 112 and 113 so that fluid is exhausted from the left end of the valve through port 101, groove 106, port 113, groove 118, port 112, passage 107, to chamber P to the sump 48. In the FIG. 9 position, the spool connects port 98, groove 91, to port 97, and opening 116 in plate 76 to pressurize chamber portion 77b for effecting movement of the vane and thereby the agitator in a counterclockwise direction.

It will be apparent from the above description that the vane motor is controlled to provide oscillating movement of the vane, and thereby the agitator, during the washing operation It will be noted ports 95 and 101 receive their signals from the vane as it rotates alternately to its extreme leftand right-hand positions respectively shown in FIGS. 7 and 9, the ports receiving uid under pressure from respective passages 105 and 106. When lluid under pressure is received in one end of the valve chamber through one of the ports, fluid is exhausted through the other port at the other end of the valve chamber. Occasionally a false signal may be sent to the valve assembly causing the valve spool to make a partial shift. The false signal may occur due to leakage between the passages. For example, should port (FIG. 7) have a leakage giving initial pressure to the right end of the valve spool, as soon as the vane rotates to a position for the exhaust signal to be reached for port 101, the valve spool will partially fire with the consequence the spool may be located in a position blocking entrance of uid under pressure through port 98 to the passages 97 and 99 causing the vane motor to become inoperative or, alternatively, in other partially red positions, cause a short stroke of the vane and agitator.

The present invention is directed to hydraulic toggle control means for the distributing valve 42 eifective to insure movement of the valve spool 86 to each of its vane-controlling positions and provided by two ports 135 and 136 in the valve block 64 respectively connected by passages 137 and 138 in the valve block to the passage 102 providing fluid under constant pressure from the port 98 connected to the pump, the ports 135 and 136 being adjacent to but spaced similar distances from the respective ports 95 and 101. Bearing in mind the previous description of the hydraulic circuits and operation of the vane in signalling the valve assembly, it is noted the additional ports 135 and 136 are arranged such that when the valve spool is displaced by a false signal from a rst motor-controlling position toward the second motor-controlling position, the additional port adjacent the first position will be opened to provide supplemental uid under pressure effective to force the valve to and holding it in its second position While simultaneously closing the second additional port. This action is reversed when the valve spool is initially displaced toward the first position as by a spurious signal from the opposite end of the valve spool in the second motorcontrolling position, thus providing a toggle action of the valve spool assisting in full valve movement preventing a short stroke of the hydraulic motor vane and also preventing any possibility of the valve spool being partially 1tired to such position that the valve spool is disposed in centered relation with the land 89 of the valve spool blocking the pressure port 98 with consequent operational failure of the vane motor. It is also apparent that, as port 135 is being opened in FIG. '7, port 136 is being closed so that uid under pressure from port 136 will not cancel or buck out the pressure from port 135 because the uid pressure in the valve chamber is being dumped from port 101 to passage 106, ports 113 and 112, passage 107 and to the sump 48.

A further advantageous feature of my improved control valve arrangement of the present hydraulic transmission is that the valve spool has snap-acting movement to each of its motor-controlling positions providing au hydraulic toggle effective -to substantial-ly instantaneously reverse the direction of rotation of the agitator.

It is important to note .that my control valve arrangement preferably, but not necessarily, includes a reciprocating spool type valve using a constant pressure source adjacent each end of the valve chamber to achieve an hydraulic toggle action, differing from mechanically-activated toggle valves or ball or spring activated detents or over-center springs engaging and controlling movement of a distributor valve.

Referring to FIG. 7, to obtain operation of the transmission to effect -rotation of the basket for the spinextract cycle, the direction of rotation of the motor is reversed and thereby the pump rotors 67 and 68 are rotated in the counterclockwise direction. As a result, the pump is eifective to provide uid under pressure to port 72 of its housing 69a. The spring 9, supplemented by the pressure fluid, actuates valve member 8 of valve 45 l(FIG. 2) to closed position `and thereby pressure fluid, in chamber C of valve 45, acts on the valve member 121 to move it in the passage to permit ilow of the uid through the flow-restricting groove 124 iu the valve member and passage 120 to the port 73 of the pump. As fluid pressure is relieved on the hydraulic lock 43, the spring 134 actuates the plunger 129 to disconnect the transmission from the stationary plate 131.

When the uid is trapped by the closure of valve 45, and allowed to recirculate through the valve housing and pump through the fiuid-iiow restricting groove l124, this restrictive action develops an orifice effect providing a reaction torque on the pump housing to rotate the housing and, through its previously-described connection to the basket 13, the basket in the direction of rotation of the motor 32. As the basket, in effect, is directly connected to the electric drive motor 32, through the hydraulic coupling provided by the pump, the basket rotates at a speed effective to provide spin-extract drying of the clothes.

What is claimed is:

1. A hydraulic system comprising a hydraulic pump; a hydraulic motor connected to be supplied with fiuid under pressure by said pump; control means including a valve having a movable member reciprocal by fluid under pressure from said pump to two motor-controlling positions each directing uid from said pump to said motor, said control means including means yfor directing additional fiuid under pressure from said pump to said valve member during movement of said valve member to each of its two motor-controlling positions, said motor controlling the iiow of fluid under pressure from said pump to said valve member to reciprocate said valve member, said motor including fluid-diverting control means operative, upon location of said valve member in each of its motor-controlling positions, to direct fluid under pressure to said valve member to move `said valve member to its other motor controlling position.

2. A hydraulic system as defined in claim 1 wherein said motor includes a housing having an oscillatable vane, and said fluid-diverting control means are in said housing and connected to said pump and controlled by said vane for alternately supplying fluid under pressure to opposite ends of said valve member to reciprocate said valve member to each of its motor-controlling positions.

3. A hydraulic system comprising a hydraulic pump; a hydraulic motor connected to be supplied with fluid under pressure by said pump; control means including ta valve having a movable member reciprocal by fluid under pressure from said pump to two motor-controlling positions each directing fiuid from said pump to said motor, said control means including means for directing additional fluid under pressure from said pump to said member during movement of said member to each of its two motor-controlling positions, said motor controlling the flow of fluid under pressure lfrom said pump to said member to reciprocate said member, said valve having a chamber for said member, and primary passages connected to opposite ends of said chamber, and said motor controlling fiow of fluid from said pump alternately to said primary passages to reciprocate said member, and said ladditional fluid-directing means includes auxiliary passages communicating with said chamber land spaced from the ends of said chamber and respectively connectable to said pump upon reciprocal movement of said member to direct additional iiuid under pressure to said member.

4. In a hydraulic system, a hydraulic pump; a hydraulic motor connected to be supplied with fluid under pressure by said pump; control means including a valve having a movable member reciprocal by fiuid under pressure from said pump to two motor-controlling positions each directing fluid from said pump to said motor, said control means including means for directing additional fluid under pressure from said pump to said member during movement of said member to each of its two motor-controlling positions, said motor controlling the flow of fluid under pressure from said pump to said member to reciprocate said member, said valve having a chamber for said member, and said additional fluid-directing means including auxiliary passages communicating with said chamber and spaced from the ends of said chamber and respectively connectable to said pump upon reciprocal movement of said member to direct additional fluid under pressure to said member; primary passages in said valve and connected to opposite ends of said chamber, with said motor controlling flow of fluid from said pump alternately to said primary passages to reciprocate said member; and .said auxiliary passages being arranged in said chamber with respect to said member that partial displacement of said member from either motor-controlling position toward the other motor-controlling position, by leakage of pressure fluid between said primary passages, uncovers one of said auxiliary passages to provide 'additional fluid under pressure to said member to force said member toward, and to hold said member in, its other motor-controlling position while simultaneously closing the other auxiliary passage thereby providing a hydraulic toggle action -to said member.

S. A hydraulic system comprising Ia hydraulic motor having a chamber provided with ports at opposite ends thereof, and an actu-ator reciprocal in said chamber; a valve including a cylinder having a centr-al port and exhaust ports intermediate ,the ends thereof, said central port being connected to a sou-ree of fluid under constant pressure, and -a spool in said valve cylinder and movable in opposite directions to two 4motor-controlling positions operative to alternately connect said central pressure port to each motor chamber port to reciprocate said actuator while connecting respective exhaust ports to the other motor chamber port, passage means adjacent each end of said motor chamber yand connected to the ends of said valve cylinder, said actuator alternately connecting each of said pass-age means to said central pressure port to move said spool in opposite directions, said valve cylinder having first and second auxiliary pressure ports adjacent opposite ends thereof and connected to said central pressure port, said rst auxiliary port being covered by `said spool in its first motor-controlling position and said second auxiliary port being covered by said spool in its second motor-controlling position, movement of said spool from either of said positions toward the other position covering one of said auxiliary ports while uncovering the other auxili-ary port to provide -additional liuid under pressure to move said spool to said other position.

6. In a hydraulic drive arrangement for a clothescleaning machine having a clothes basket and an agitator in said basket, the drive arrangement comprising a housing; a pump in said housing; a hydraulic moto-r in said housing `and having a fluid chamber, and an oscillatable vane in said chamber and connected to said agitator; a valve controlling oscillation of said vane and including a cylinder having a central pressure port connected to said pump, first and second exhaust ports between the ends of said cylinder, and first and second auxiliary ports, and a valve spool reciprocal in said cylinder; means defining first and second passages in said housing and respectively connected to said chamber at opposite sides of said vane, movement of said v-alve spool providing for said passages -being alternately connectible to said central pressure port and to respective exhaust ports to oscillate said vane; means defining third yand fourth passages in said housing and connected to said pressure port and respectively connected to opposite ends of said cylinder, said vane diverting fluid under pressure from said pressure port alternately to each of said third and fourth passages to move said valve spool in opposite directions to first and second vane-controlling positions while fluid is exhausted from said chamber by said vane through the other of said third and fourth passages; means defining fifth and sixth passages in said housing and connecting said pressure port to said first and second auxiliary ports in said cylinder, and said first auxiliary port being located adjacent one end of said cylinder between said first exhaust port and said third passage in said cylinder and said second auxiliary port being located adjacent the other end of said cylinder between said second exhaust port and said fourth passage in said cylinder, partial movement of said spool by liuid under pressure from said third passage toward its rst vane-controlling position uncovering said first auxiliary port to provide additional fluid under pressure to said spool 'to move said spool with a snapaction -to its rst vane-controlling position and to hold said spool in its first vane-controlling position While closing said second auxiliary port, and partial movement of said spool by uid under pressure from said fourth passage toward its second vane-controlling position uncovering said second auxiliary port to provide additional uid under pressure to said spool to move said spool to its second vaneacontrolling position with a snap-action and to hold said spool in its second vane-controlling position, said auxiliary ports cooperating with said spool to alternately provide lluid under presure to reciprocate said spool thereby providing a hydraulic toggle action to said spool.

References Cited UNITED STATES PATENTS EDGAR W. GEOGHEGAN, Primary Examiner 

